Higher-Order Monitoring of Physiological Field Fluctuations in Brain MRI at 7T

Signe Johanna Vannesjo¹, Christoph Barmet¹, Yolanda Duerst¹, Simon Gross¹, David O. Brunner¹, Klaas P. Pruessmann¹

Field fluctuations caused by breathing and limb motion can have a strong degrading effect on quality of brain images at high fields. Partly, the resulting artifacts can be corrected for by proper f0-demodulation of the object signal, based on field data from navigators or concurrent field monitoring. In this work, we investigate the contribution of higher-order field components to the perturbations, and use concurrent field monitoring up to 2nd order to additionally improve image quality in high-resolution T2*-weighted GRE sequences.e 2nd-order concurrent field monitoring to correct for induced artifacts.